The neighborhood watch volunteer, who fatally shot an unarmed black teenager in a racially charged encounter in central Florida, was cleared of all charges tonight.

The jury of six women delivered the verdict after 16 hours of deliberations — including 12 hours today.

Zimmerman sat stone-faced when the verdict was read, and then he nonchalantly shook hands with his lawyers.

Seminole County Court Judge Debra Nelson admonished audience members to keep reactions to themselves — and they did, as no one uttered a peep when the words “not guilty” were read.

The case became a lightning rod of racial politics as the country debated whether Zimmerman’s claim — that he feared for his life — justified his killing of unarmed Trayvon Martin, who was walking home from the store.

In a controversial decision, Judge Nelson allowed the jury to consider convicting Zimmerman on a manslaughter charge, which would require a lesser burden of proof and carries a prison sentence of up to 30 years.

A 911 call captured someone screaming for help during the Feb. 26, 2012 attack, though no one could definitively say who was crying out. Martin’s family claimed the voice was that of their son, while Zimmerman’s relatives asserted it was George calling for aid.

Testimony from voice-recognition experts had been ruled inadmissible because it was impossible to tell from the brief, poor-quality recording whether it is Martin or Zimmerman calling for help.

Martin’s deathbrought national attention to Florida’s “Stand Your Ground” laws, inspired the “Million Hoodie March” and prompted President Barack Obama to call the case a “tragedy.”

“If I had a son, he’d look like Trayvon,” Obama said in March 2012.”

A neighborhood watch coordinator in a gated community in Sanford, Fla., Zimmerman was running an errand on a rainy night when he spotted Martin, wearing a hooded sweatshirt and walking around.

Zimmerman, then 28, called police to report what he said was a “suspicious” person.

“This guy looks like he’s up to no good, or he’s on drugs or something,” Zimmerman said on the recorded call.

Zimmerman complained of break-ins in the neighborhood, adding: “These —holes, they always get away,” according to 911 recordings.

Martin was living in the Retreat at Twin Lakes temporarily, and was returning from a snack run to a nearby 7-Eleven when Zimmerman spotted him.

The teen was talking to Jeantel on his cell phone while he walked home.

Jeantel said Martin was frightened of the strange man following him and tried to run home — prompting Zimmerman to leave his car and give chase even though dispatchers told him to stay put, prosecutors charged.

What followed was a deadly confrontation in which the unarmed teen allegedly punched Zimmerman in the nose, and eventually overpowered the older man, standing over him and allegedly slamming his head into the sidewalk, Zimmerman claimed.

That’s when Zimmerman, allegedly fearing for his life, shot and killed the teen.

Forensic evidence and witnesses, who spoke at trial, backed Zimmerman’s contention that Martin had been standing over him during their struggle.

It took police in Sanford, Fla., about 30 minutes north of Orlando, 44 days to arrest Zimmerman, as local cops accepted his claims of self-defense – citing Florida’s 2005 “Stand Your Ground” laws as reason not to arrest him.

As outrage over the case grew and cries of racism came from all corners of the nation, a special prosecutor was appointed and accused Zimmerman of racial profiling, charging him with second-degree murder. He later turned himself in.

Zimmerman did not testify during the two-week trial.

The all-female jury has been sequestered.

Most members of the panel are married with children. Only one of the jurors, a married mom who works as a nurse, is black.

The rest of the panel, identified during the trial only by assigned numbers, included a retired, single woman without kids who worked in real estate; a property manager; a volunteer animal rescuer; a safety office who recently moved to Florida from Iowa and a woman who worked in financial services.

With Post Wire Services and additional reporting by David K. Li and Laura Italiano